Simply place the tool or object you want to magnetize inside the coil and briefly press S1. The generated single polarity field should magnetize the object if the material it is made to allow.
This circuit triggers the LED when the monitored battery voltage drops below 9 V for 12 V...
We found this circuit in a Radio Electronics from January 1967. The SCR is already the C106, which...
This power source with silicon diodes at a time when valves were still used was found in Radio...